Arcen is on Christmas Holiday, as mentioned elsewhere I believe. They are also focused on getting AVWW2 done, including Keith if I recall. As for Ancient Shadows not being balanced, keep in mind you are comparing that to all the other expansions that has been part of massive patch changes over years. Relative to that, Ancient Shadows will of course feel less balanced. Arcen Games is so good at patching and communicating that we can get spoiled when they work on a different project than the one we are interested in, or when a holiday comes up. But it will all work out. They've got a pretty good track record stretching back years of getting their stuff nicely balanced.
As for RAID, that affects only a single Super Weapon (Hive Golems). It was added because getting a Hive Golem meant you didn't need to fight the home worlds because the Hive Golem would auto-kill them, the Wasps were so effective. So instead of nerfing Wasps, a counter was added to Home Worlds. Maybe the new Brutal Picks, especially in Ancient Shadows means Hive Golems aren't the home world killers they used to be before RAID, but I wouldn't bet on it. On top of that, you can trigger RAID intentionally to counter Spawners, so Hive Golems are still useful on home world assaults.
And from personal experience, Ancient Shadows is winnable on 9/9. Of all the balance tweaks, I feel Astro Trains need the most as I don't even think they are workable at 4.